Replacement filters are $39.00 except for the GT500 filter which is $45.00 and the Hemi System filter which is $49.00. Replacement air filters for all C&L 2005-2008 Mustang GT, Shelby GT500, Mustang V6, 03-04 MACH1 and 03-04 COBRA Air Induction Systems. Filters for C&L 73mm and 76mm Mass Air Flow Housings and C&L Filter Kits also available.